Rotary tooth brush



Aug. 29, 1939. G. F.,w. KING 2,171,308

ROTARY TO OTH BRUSH Filed Jan. 26, 1937 W96 fW/ff .N E*

ATTORNEYS Patented Aug. 29, 1939 UNITED STATES PATENT OFFICE 1 Claim.

'Ihis invention relates to rotary tooth brushes and has for the primary object the provision of a simple and inexpensive device of this character which will permit thorough cleaning of teeth and the spaces therebetween and which may be easily operated by comparatively short thumb and linger movements and may be successfully used by either hand of a person.

With these and other objects in view, this invention consists in certain novel features of construction, combination and arrangement of parts to be hereinafter more fully described and claimed.

For a complete understanding of my invention, reference is to be had to the following description and accompanying drawing, in which Figure 1 is a side elevation illustrating a tooth brush constructed in accordance with my invention. Figure 2 is a sectional View taken on the line 2-2 of Figure 1.

Figure 3 is a transverse sectional view taken on the line 3-3 of Figure 2.

Referring in detail to the drawing, the numeral I indicates a sleeve slidably received within a cylinder 2, one end of which is closed by a movable cap 3 having formed integrally therewith a ring or eye 4 through which may be positioned a persons thumb. The other end of the cylinder or the end which slidably receives the sleeve I has an internal shoulder 6 to be abutted by a flange 1 formed on one end of the sleeve for limiting the movement of the sleeve outwardly of the cylinder. Rotatably supported and extending through the sleeve I is a shaft 8, a portion of which has a bore 9 to receive a coil spring I0. Slidably received within the bore Ill and also within the spring is a guide rod II having fitting engagement with a bearing I2 formed on the inner face of the cap 3. The purpose of the guide rod II is to prevent the spring bending out of shape or kinks forming therein during the use of the device.

445l A feed nut I3 is keyed or otherwise secured to the shaft 8 andmeshes with feed threads I4 formed in the cylinder 2. Secured to the shaft l in any suitable manner is a shank I5 carrying a series of tufts of bristles I6. A collar I1 is (c1. 'zi-ss) threaded to the sleeve I and has formed thereon nger rests I8. A shoulder I9 is formed on the sleeve to cooperate with a thrust collar 20 formed on the shaft.

The bristles during non-use of the device are 5 protected by a casing 2I and the latter has locking grooves 22 to receive lugs 23 formed on the collar I1 thereby removably securing the casing to the sleeve with the bristles confined therein.

In use, the casing 2| is removed and the oper- 10 ator places two fingers against the finger rests I8 and the thumb in the ring 4 and by moving the thumb towards the fingers the cylinder 2 will be slid on the sleeve I. The relative sliding movement between the cylinder 2 and the sleeve I 15 brings about rotation of the shaft 8 due to the feed nut meshing with the feed threads of the cylinder, consequently the bristles are rotated and when placed against the teeth and moved upwardly and downwardly with the rotary mo- 20 tion will thoroughly remove foreign matter from the teeth and from the spaces between the teeth.

The thumb and finger motion above described causes rotation of the brush in one direction compressing the spring I0, and the brush is rotated 25 in the reverse direction by the expansion of the spring when the thumb pressure is released on the ring 4.

Having described the invention, I claim:

A rotary toothbrush comprising a sleeve, a 30 shaft journaled'in said sleeve and fashioned with a hollow section and adapted to have a work implement secured thereto, a cylinder slidably mounted on said sleeve andprovided with feed threads formed in the bore thereof, a feed nut 35 fixed to said shaft and meshing with said threads,

a coil spring extending into said hollow section of said shaft and bearing against one end of said cylinder for rotating said implement upon expansion of said spring from compressed condition 40 in said section, said sleeve and cylinder manually actuatable towards each other for rotating said implement in' the opposite direction and compressing said spring, and a guide rod carried by said cylinder and extending through said spring into said section to maintain said spring in aligned relation with said section.

GEORGE F. W. KING. 

